1. Technical Field
The present invention relates to an electro-optical device including an organic EL (electro luminescent) element, a liquid crystal a method for driving thereof, and electronic apparatus.
2. Related Art
In the past, an electro-optical device including organic EL elements as an electric optical element has been provided. The electro-optical device is provided with various drive circuits for supplying a predetermined current or voltage to the organic EL elements or the like. Such a drive circuit, for example, often includes capacitative elements connected in parallel with the organic EL elements. In this case, a data potential is supplied to the anode of the organic EL element and one electrode of the capacitative element, and a reference potential is supplied to the cathode of the organic EL element and the other electrode of the capacitative element. With this configuration, a current based on accumulated electric charges in the capacitative element, that is, data potential, can be performed to the organic EL element, so that stable drive or the like of the organic EL element can be performed.
As such an electro-optical device, a device disclosed in JP-A-2000-122608, for example, is known.
Meanwhile, the following problems exist in the above-described electro-optical device. Specifically, to make a light emission amount (a time integral value of light emission brightness) of the organic EL element become a sufficient value, a charge amount accumulated in the capacitative element needs to be increased. Therefore, it is necessary to make the capacitance of the capacitative element become a very large value. However, because a physical area allowed for each drive circuit is limited, it is difficult ever to realize such a large capacitance value.
Accordingly, in order to solve the problem, a technique is disclosed in U.S. Patent Application Publication No. 2009/0195534. In the technique, capacitative elements, each included in respective drive circuit (unit circuit), are used for driving one organic EL element. In a simple example, in the case where drive circuits are arranged in one line and the number of the circuits is N (therefore, the number of the capacitative elements and the number of the organic EL elements are both N), in driving one organic EL element, firstly, charging in response to data potential corresponding to the organic EL element is performed simultaneously to N-pieces of capacitative elements included in all drive circuits, and secondly, simultaneous discharging (more specifically, current supply) of the N-pieces of capacitative elements is performed to the organic EL element.
With this configuration, the above-mentioned inconvenience becomes negligible.
However, there is still a room for improvement in such a technique. Specifically, according to the above-mentioned example, simultaneous charging and simultaneous discharging to all of N-pieces of capacitative elements are performed to drive one organic EL element, and at each point of charging and discharging, an extremely large current may be generated instantaneously. Such a problem could be more serious as the number of capacitative elements or the number of drive circuits becomes larger. Therefore, if such large current may be generated, a problem occurs that noise associated with the current is generated, and as a result, properly controlled operation for all drive circuits becomes difficult, or adverse effect or the like to peripheral equipment due to the noise radiation will be concerned.